Dynamic electronic door lock control system

ABSTRACT

A method of controlling access to a real estate property includes installing a dynamic electronically-controlled lockset on an exterior door of a real estate property, maintaining, at a remote location, a reference device adapted to present a value of a second dynamic access code to one or more users located in the real estate office, receiving, at the real estate agent location, a request from a user for a current value of the second dynamic access code, examining the reference device to determine the current value of the second dynamic access code, and providing the current value of the second dynamic access code to the user for input into the electronically-controlled lockset. The lockset is adapted to unlock upon receiving a value corresponding to a first dynamic access code programmed therein. The second dynamic access code is time-synchronized with the first dynamic access code programmed in the electronically-controlled lockset.

CROSS-REFERENCE TO RELATED APPLICATIONS

The present application is a continuation of U.S. nonprovisional patentapplication Ser. No. 13/485,852, filed on May 31, 2012, which itself isa continuation-in-part of U.S. nonprovisional patent application Ser.No. 13/354,283, filed on Jan. 19, 2012, which itself is acontinuation-in-part of U.S. nonprovisional patent application Ser. No.11/749,743, filed on May 16, 2007, which itself claims priority to U.S.provisional patent application Ser. No. 60/747,410, filed on May 16,2006. Each of the foregoing applications is incorporated by referenceherein in its entirety.

COPYRIGHT STATEMENT

All of the material in this patent document is subject to copyrightprotection under the copyright laws of the United States and of othercountries. The copyright owner has no objection to the facsimilereproduction by anyone of the patent document or the patent disclosure,as it appears in the Patent and Trademark Office patent file or records,but otherwise reserves all copyright rights whatsoever.

BACKGROUND OF THE PRESENT INVENTION

1. Field of the Present Invention

The present invention relates generally to real estate door lock controlsystems, and, in particular, to a dynamic electronic door lock controlsystem using periodically changing access codes.

2. Background

Builders have traditionally contracted with real estate agents torepresent them in the sale of their new homes with the expectation thatagents would provide access, sales and security. They count on agents tofacilitate the showing of their new properties to prospective buyers,with or without the accompaniment of the agents themselves. In largesubdivisions with dozens of new homes being built, agents are available“on-site” certain hours of the day to open and sell these new homes, andkeep the properties secure.

However, with the dearth of areas suitable for large developments todayin many markets, builders are constructing “infill” homes, that is, newhomes in existing neighborhoods. Currently, agents mount a mechanicalkey-holding device on the front door of such properties to provideaccess to other agents. These other agents have a personal device whichthey use to interact with the doorknob-mounted device to open it and toaccess a key to the front door of the property. As they leave, they lockthe door and place the key back in the doorknob-mounted device.

For a buyer without a buyer's agent to tour a newly built home, he/shecalls the listing agent of record and requests a tour. The agenttypically has to drive over to the property immediately to open the homefor the prospective buyer, or set an appointment to meet there at alater time. Because of the hassles involved, buyers often do not call anagent for a tour unless they have exceptional interest. Agents find it ahassle to have to drop everything to show these homes, often only todiscover the buyers to be “tire-kickers.” Agents with multipleproperties must devote a considerable amount of time to this processwith little return on their investment of time and money. As a result,builders' properties are not shown as often as they would like. Indesperation, some builders encourage buyer tours by unlocking theirmostly completed homes during the daylight hours and locking them backup every night. They know that buyers need to explore/touch/see thehouses in order to have interest in and come to buy a property.

At the current time in the real estate market, there is not a keylesslock that works on a time rotation or sequence-based code, which couldbe used for Builder's new properties. The products that are availableinvolve (1) opening a box and extracting a key or (2) keyless unlockingvia a punched in code but the code in the lock has to be changedmanually if it can be changed at all. Both present significant securityrisks since both the key and the unchanged code could fall into thewrong people's hands. Thus, a need exists for a dynamic electronic doorlock control system using periodically-changing access codes to controlaccess to properties being offered for sale or lease.

SUMMARY OF THE PRESENT INVENTION

The present invention would allow access, sales and security of a newproperty without an agent having to be present. Builders' propertieswould be more accessible to buyers without agents. Builders would have aclearer picture of the buyers touring their properties and post-tourfeedback from the buyers. They would not have to risk leaving theirproperties unsecured in order to encourage tours. Agents would be ableto avoid last-minute scheduling snafus, handle more “infill” propertiesat a time, could serve the builders better in terms of qualifyingprospective buyers before letting them in the home, and benefit fromhaving the buyer's cell phone or home number for follow-up feedback andpossible other-tour sales. Further advantages could be realized in awide variety of other real estate contexts, including traditional newdevelopments, commercial properties, vacation rentals, and the like, allas described herein.

Broadly defined, the present invention according to one aspect is amethod of controlling access to a real estate property, including:installing a dynamic electronically-controlled lockset on an exteriordoor of a building constituting a real estate property, the locksetbeing adapted to unlock upon receiving, as input, a value correspondingto a first dynamic access code programmed therein; maintaining, at areal estate agent location that is located remotely from the real estateproperty, a reference device adapted to present a value of a seconddynamic access code to one or more users located in the real estateoffice, the second dynamic access code being time-synchronized with thefirst dynamic access code programmed in the electronically-controlledlockset; receiving, at the real estate agent location, a request from auser for a current value of the second dynamic access code; examiningthe reference device to determine the current value of the seconddynamic access code; and providing the current value of the seconddynamic access code to the user for input into theelectronically-controlled lockset.

In further features of this aspect, the method further includesreceiving, by the electronically-controlled lockset, the current valueof the second dynamic access code as input by the user, and if thereceived value of the second dynamic access code is the same as thefirst dynamic access code, unlocking the lockset; and the method furtherincludes the steps of changing, on a periodic basis, the value of thefirst dynamic access code, and changing, on a periodic basis, the valueof the second dynamic access code such that the value of the seconddynamic access code remains synchronized with the value of the firstdynamic access code.

In another feature of this aspect, the method further includes the stepof preventing an unauthorized user from retrieving the first dynamicaccess code from the electronically-controlled lockset.

In another feature of this aspect, the step of installing includesinstalling a dynamic electronically-controlled lockset having a housingthat encloses an electronics assembly including a control module thatreceives inputs from both an electronic code module and a user inputdevice. In a further feature of this aspect, the method further includescomparing, by the control module, the received value of the seconddynamic access code to the first dynamic access code.

In another feature of this aspect, the method further includes the stepof generating each value of the first dynamic access code using apseudorandom number generation algorithm. In another feature, the methodfurther includes the step of generating each value of the second dynamicaccess code using the same pseudorandom number generation algorithm thatis used to generate each value of the first dynamic access code. Instill another feature, generating each value of the first and seconddynamic access codes includes incorporating a value representative of acurrent time and a value identifying the lockset.

In another feature of this aspect, the step of maintaining a referencedevice includes maintaining the reference device at a real estate officethat is located remotely from the real estate property.

In another feature of this aspect, the step of maintaining a referencedevice includes maintaining the reference device on the person of a realestate agent located remotely from the real estate property.

In another feature of this aspect, the step of examining the referencedevice includes examining a digital display hat visually presents thecurrent value of the second dynamic access code.

The present invention according to another aspect is a dynamicelectronic door lock control system, including: a dynamicelectronically-controlled lockset, the lockset including a user inputdevice, a lock interface operable to unlock a door if the locksetreceives, via the user input device, input, in the form of a value, thatmatches a first dynamic access code residing internally in the locksetand not made readily available to unauthorized users; and a referencedevice including a user interface for presenting, to a user, a currentvalue of a second dynamic access code residing internally in thereference device; wherein the first dynamic access code and the seconddynamic access codes are synchronized such that they change frequentlyand at substantially similar points in time.

In features of this aspect, the first and second dynamic access codeschange on a regular periodic basis such that the value of the seconddynamic access code remains synchronized with the value of the firstdynamic access code; and the dynamic electronically-controlled locksetincludes a housing that encloses an electronics assembly including acontrol module that receives inputs from both an electronic code moduleand a user input device.

In another feature of this aspect, the lock interface is connected tothe control module and responsive to one or more control signalsprovided by the control module.

In another feature of this aspect, the lock interface is operable tounlock the door if the inputs from both the electronic code module andthe user's input device are substantially similar.

In another feature of this aspect, the input provided by the electroniccode module to the control module is representative at any time of thevalue of the first dynamic access code.

In another feature of this aspect, the electronic code module includes apseudorandom number generator using an algorithm to generate a sequenceof first dynamic access code values. In further features, the referencedevice includes a pseudorandom number generator using the same algorithmto generate a sequence of second dynamic access code values; and eachvalue of the first and second dynamic access codes incorporates a valuerepresentative of a current time and a value identifying the lockset.

In another feature of this aspect, the reference device is portable. Ina further feature, the second dynamic access code provided by theportable reference device must be presented via a user input device ofthe electronically-controlled lockset within a limited time window inorder to cause the lockset to unlock.

In another feature of this aspect, the reference device includes adigital display which visually presents a current value of the seconddynamic access code.

The present invention according to another aspect is a method ofcontrolling access to the interior of a real estate property, including:installing a dynamic electronically-controlled lockset on an exteriordoor of a building constituting a real estate property, the locksetbeing operable to unlock the door if a user enters a sequence of numbersinto the lockset corresponding to a first dynamic access code residinginternally in the lockset and not made readily available to unauthorizedusers; providing a reference device to a listing agent; makinginformation available to persons seeking to gain access to the interiorof the building as to how to make contact with the listing agent; whenthe listing agent receives contact from a particular person seeking togain access to the interior of the building, determining whether toapprove the particular person for interior access to the building; ifthe particular person is approved for interior access to the building,providing, by the listing agent, a second dynamic access code to theparticular person, wherein the second dynamic access code issynchronized with the first dynamic access code contained within thelockset, the first and second dynamic access codes being synchronizedsuch that they change at substantially similar points in time.

The present invention according to another aspect is a business methodof building and/or securing market share for real estate agents listingproperties for sale or lease, including: granting, by a distributor,rights to a real estate agent to utilize a dynamic electronic door lockcontrol system in a particular, defined geographic area, the rightsbeing applicable only in the particular, defined geographic area;providing multiple units of a dynamic electronically-controlled locksetto the real estate agent, each for mounting on an exterior door of abuilding constituting a real estate property and for controlling accessto the interior of the building thereby, the lockset being adapted toopen upon receiving, as input, a sequence of numbers corresponding to anaccess code programmed therein; and providing at least one referencedevice to the real estate agent, the reference device being synchronizedwith one or more of the multiple dynamic electronically-controlledlocksets such that the reference device may be examined to determine thecurrent value of an access code that may be entered into the one or morelocksets in order to gain access to a respective building.

The present invention according to another aspect is a business methodof managing interior access to a plurality of real estate properties,including: providing multiple units of a dynamicelectronically-controlled lockset to a plurality of real estate businessentities, each for mounting on an exterior door of a buildingconstituting a real estate property and for controlling access to theinterior of the building thereby, the lockset being adapted to open uponreceiving, as input, a sequence of numbers corresponding to an accesscode programmed therein; establishing a call center for receivinginterior access requests from a plurality of interested individuals; andproviding at least one reference device to the call center, thereference device being synchronized with one or more of the multipleunits of the dynamic electronically-controlled locksets such that thereference device may be examined to determine the current value of anaccess code that may be entered into the one or more locksets in orderto gain access to a respective building.

Further areas of applicability of the present invention will becomeapparent from the detailed description provided hereinafter. It shouldbe understood that the detailed description and specific examples, whileindicating the preferred embodiment of the invention, are intended forpurposes of illustration only and are not intended to limit the scope ofthe invention.

BRIEF DESCRIPTION OF THE DRAWINGS

The features of the various embodiments of the present disclosure willbecome apparent from the following detailed description with referenceto the drawings. The components in the drawings are not necessarily toscale, with emphasis instead being placed upon clearly illustrating theprinciples of the disclosure. Moreover, in the drawings, like referencenumerals designate corresponding parts throughout the several views.

FIG. 1 is a simplified illustration of a suburban neighborhood in whicha small infill-type development, consisting of a small number of newhouses, is being constructed in between existing houses.

FIG. 2 is a block diagram of a dynamic electronic door lock controlsystem in accordance with the various embodiments of the presentdisclosure.

FIG. 3 is a perspective view of the dynamic electronically-controlledlockset of FIG. 2.

FIG. 4 is a block diagram of electronic components of the dynamicelectronically-controlled lockset of FIG. 3.

FIG. 5 is a front view of the reference device of FIG. 2.

FIG. 6 is a flowchart illustrating steps of a process carried out by alockset according to various embodiments of the present disclosure.

FIG. 7 is a flowchart illustrating steps of a process carried out by alockset according to various embodiments of the present disclosure.

FIG. 8 is a very simplified flowchart diagram of the steps of a processcarried out by users in using the lock control system.

FIG. 9 is a block diagram of a dynamic electronic door lock controlsystem in accordance with another embodiment of the present invention.

FIG. 10 is a block diagram of a dynamic electronic door lock controlsystem in accordance with yet another embodiment of the presentinvention.

FIG. 11 is a set of simplified flowchart diagrams illustrating differentapproaches for operation of an electronically-controlled lockset.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

As a preliminary matter, it will readily be understood by one havingordinary skill in the relevant art (“Ordinary Artisan”) that the presentinvention has broad utility and application. Furthermore, any embodimentdiscussed and identified as being “preferred” is considered to be partof a best mode contemplated for carrying out the present invention.Other embodiments also may be discussed for additional illustrativepurposes in providing a full and enabling disclosure of the presentinvention. Moreover, many embodiments, such as adaptations, variations,modifications, and equivalent arrangements, will be implicitly disclosedby the embodiments described herein and fall within the scope of thepresent invention.

Accordingly, while the present invention is described herein in detailin relation to one or more embodiments, it is to be understood that thisdisclosure is illustrative and exemplary of the present invention, andis made merely for the purposes of providing a full and enablingdisclosure of the present invention. The detailed disclosure herein ofone or more embodiments is not intended, nor is to be construed, tolimit the scope of patent protection afforded the present invention,which scope is to be defined by the claims and the equivalents thereof.It is not intended that the scope of patent protection afforded thepresent invention be defined by reading into any claim a limitationfound herein that does not explicitly appear in the claim itself.

Thus, for example, any sequence(s) and/or temporal order of steps ofvarious processes or methods that are described herein are illustrativeand not restrictive. Accordingly, it should be understood that, althoughsteps of various processes or methods may be shown and described asbeing in a sequence or temporal order, the steps of any such processesor methods are not limited to being carried out in any particularsequence or order, absent an indication otherwise. Indeed, the steps insuch processes or methods generally may be carried out in variousdifferent sequences and orders while still falling within the scope ofthe present invention. Accordingly, it is intended that the scope ofpatent protection afforded the present invention is to be defined by theappended claims rather than the description set forth herein.

Additionally, it is important to note that each term used herein refersto that which the Ordinary Artisan would understand such term to meanbased on the contextual use of such term herein. To the extent that themeaning of a term used herein—as understood by the Ordinary Artisanbased on the contextual use of such term—differs in any way from anyparticular dictionary definition of such term, it is intended that themeaning of the term as understood by the Ordinary Artisan shouldprevail.

Furthermore, it is important to note that, as used herein, “a” and “an”each generally denotes “at least one,” but does not exclude a pluralityunless the contextual use dictates otherwise. Thus, reference to “apicnic basket having an apple” describes “a picnic basket having atleast one apple” as well as “a picnic basket having apples.” Incontrast, reference to “a picnic basket having a single apple” describes“a picnic basket having only one apple.”

When used herein to join a list of items, “or” denotes “at least one ofthe items,” but does not exclude a plurality of items of the list. Thus,reference to “a picnic basket having cheese or crackers” describes “apicnic basket having cheese without crackers”, “a picnic basket havingcrackers without cheese”, and “a picnic basket having both cheese andcrackers.” Finally, when used herein to join a list of items, “and”denotes “all of the items of the list.” Thus, reference to “a picnicbasket having cheese and crackers” describes “a picnic basket havingcheese, wherein the picnic basket further has crackers,” as well asdescribes “a picnic basket having crackers, wherein the picnic basketfurther has cheese.”

Referring now to the drawings, in which like numerals represent likecomponents throughout the several views, the preferred embodiments ofthe present invention are next described. The following description ofthe preferred embodiment(s) is merely exemplary in nature and is in noway intended to limit the invention, its application, or uses.

FIG. 1 is a simplified illustration of a suburban neighborhood 10 inwhich a small infill-type development 30, consisting of a small numberof new houses 32, is being constructed in between existing houses 12. Inthis simplified illustration, the existing houses 12 utilizeconventional locksets 20 on the doors of the houses 12, while the newhouses 32 utilize dynamic electronically-controlled locksets 40 inaccordance with the preferred embodiments of the present invention.

FIG. 2 is a simple block diagram of a dynamic electronic door lockcontrol system in accordance with a preferred embodiment of the presentinvention. As shown therein and in FIG. 1, the door lock control systemincludes one or more dynamic electronically-controlled locksets 40 andat least one reference device 60. In the embodiment shown in FIG. 1,there are, in fact, three such locksets 40 and one reference device 60.However, other embodiments are likewise possible, as further discussedin a subsequent section. In the illustrated application, the dynamicelectronically-controlled locksets 40 are intended to be utilizedon-site, on the doors of the new houses 32 being constructed, while thereference device or devices 60 are intended to be used remotely, asdescribed in greater detail herein below.

FIG. 3 is a perspective view of the dynamic electronically-controlledlockset 40 of FIG. 2. In general appearance, the dynamicelectronically-controlled lockset 40 of the present invention mayresemble some conventional electronically-controlled locksets, with eachhaving a doorknob 42 carried by a housing 44 that also provides a userinput device 46. The doorknob 42, housing 44 and user input device 46may each be of conventional construction, such as aten-digit/twelve-button electronic keypad above a keyed door knob on theexterior side of the lockset 40 and a box with a matching knob on theinterior side. In various alternative variations, the user input device46 may utilize mechanical pushbuttons, electronic sensors, or the likeand may or may not be protected by a flexible membrane. In still furtheralternative variations, the user input device 46 may include a greateror lesser number of input keys or buttons or may include a single keythat may be manipulated to select from any of a plurality ormultiplicity of numbers, letters or characters. Perhaps particularlywith regard to the latter variations, an electronic display, such as aseries of digits displayed via LED or LCD technology, may further beincluded. It will be appreciated that all of these variations and anyother conventional variations thereof are included within the scope ofthe present invention.

Notably, and as further explained below, the doorknob 42 and housing 44each include one or more additional elements not illustrated in FIG. 3,but which are well known to the Ordinary Artisan. Components suitablefor use in the lockset 40 of the present invention are offered by avariety of manufacturers, and in particular are offered in the form ofthe PAKK-OIP lockset available from Luminair Products, Inc., dba KeylessPro, of La Puente, Calif.

FIG. 4 is a block diagram of the major electronic components of thedynamic electronically-controlled lockset 40 of FIG. 3. Most or all ofthe major electronic components of the lockset 40 are supported by anelectronics assembly 48, and include an interface with the user inputdevice 46, an electronic code module 50, a control module 52, a lockinterface 54 and a battery module 56. The electronics assembly 48 may bea simple printed circuit board of conventional construction. The controlmodule 52 is the center of operations for the electronics assembly 48,receiving power from the battery module 56, inputs from the user inputdevice 46 via the interface, and input from the electronic code module50. Based on the various inputs, the control module 52 outputs one ormore control signals to the lock interface 54. The lock interface 54,which may be of conventional design and construction, provides theelectromechanical interface to the lock mechanism, thereby translatinginput representative of an “unlock” instruction to mechanical motion.Such an interface 54 is likewise provided in the PAKK-OIP locksetdescribed previously.

The electronic code module 50 provides one or more signals that areinput to the control module 52, the one or more signals beingrepresentative at any time of the value of a time-based dynamic accesscode, determined or controlled by the electronic code module 50, thatmust be independently entered by a user in order to cause the controlmodule 52 to activate the lock interface 54. Notably, code values willgenerally be described herein as numerical in nature, but it will beappreciated that other types of values, including alphabetic,characters, and the like may likewise be used without departing from thescope of the present invention. It will further be appreciated thatvarious elements of the present invention as described herein maynecessarily be changed to accommodate such varying value types, butlikewise will be accomplished without departing from the scope of thepresent invention.

The dynamic access code itself is changed frequently on somepredetermined basis, and preferably changes frequently enough such thatthe same access code is never valid for more than one consecutive entryby a user. Such access codes may be determined or controlled by theelectronic code module 50 in more than one way. In a first method ofdetermining or controlling a dynamic access code, a pseudorandom numbergenerator, seeded using one or more predetermined inputs, may be used tocreate a series of pseudorandom numbers of a desired number of digits,with a resulting output value being provided to the control module 52.This output value is changed on a periodic basis, preferably at arelatively high frequency, such as once every 120 seconds. In a secondmethod of determining or controlling a dynamic access code, amultiplicity of predetermined numbers, each of a desired number ofdigits, are stored in the electronic code module 50 and output, one at atime, to the control module 52. As in the first method, the resultingoutput value is changed on a periodic basis, preferably at a relativelyhigh frequency, such as once every 120 seconds.

Other methods of determining or controlling a dynamic access code, andoutputting a resulting value on a periodic, relatively high frequencybasis, may be known to the Ordinary Artisan. An importantcharacteristic, however, is that the determination or control of thedynamic access code should be carried out in coordination with theoperation, described below, of the separate reference device 60. Suchcoordination may be achieved by reproducing, at the reference device 60,the method the electronic code module 50 uses to determine or controlthe dynamic access code that may be reproduced by the reference device60, by using a conventional wireless communication method to transmitthe dynamic access code that is determined or controlled from one of thedevices 60,50 to the other, or by other methods or technologies known tothe Ordinary Artisan. In one algorithmic approach suitable for use inthe present invention, the electronic code module 50 uses as inputs theyear, month, hour and minute from an internal clock and a three-digitvalue unique to the lockset 40 and generates a 4-digit output valueusing conventional logical operations, such as shifts, rotates, ANDs,ORs, XORs and the like. Assuming the three-digit lockset value is knownto the reference device 60 and the internal clock of the electronic codemodule 50 is synchronized with an internal clock in the reference device60, or the equivalent thereof, determination of the 4-digit output valuemay be easily duplicated by the reference device 60.

Optionally, the control module 52 may be of generally conventionalconstruction except that the value of the valid access code is providedby the electronic code module 50, and that value changes on a periodic,relatively high frequency basis. Otherwise, the control module 52 may beof the type wherein the access code at any time is a constant,non-changing (static) access code that is stored in the control module52 or in a connected storage device. The control module 52 receives asteady stream of ever-changing access code values from the electroniccode module 50. As each new access code value is received by the controlmodule 52, it is stored in a specific register, with the access codevalue that is stored in the register at any given time being understoodto be the current access code value. Alternatively, the electronic codemodule 50 may generate a steady stream of ever-changing access codevalues but may provide a current value to the control module 52 onlyupon request and which, upon receipt, is stored in the specific registeras the current access code value. In each case, the access code valuestored in the specific register remains the current access code valueuntil it is replaced with a new access code value.

Meanwhile, the control module 52 may, at any time, receive a user inputvalue via the interface with the user input device 46. In other words, auser may, at any time, input a numeric value via the user input device46, and the entered value may be provided as an input to the controlmodule 52. The control module 52 compares the user input value, asreceived from the user input device 46, with the value of the currentaccess code value, as received from the electronic code module 50 andstored in the current access code register. If the user input valuematches the current access code value, then the control module 52 sendsone or more control signals to the lock interface 54, instructing thelock interface 54 to cause the lock to be unlocked. On the other hand,if the user input value does not match the current access code value,then the lock interface 54 is effectively instructed, either explicitlyor implicitly, to maintain the lock in a locked state.

Although the electronic code module 50 may provide the current accesscode value to the control module 52 on the periodic, relatively highfrequency basis as described above, the electronic code module 50 doesnot display or otherwise provide the current access code value directlyto the user. Indeed, the electronic code module 50 preferably has nomeans for displaying or otherwise providing the current access codevalue directly to a user. Moreover, although the control module 52 oruser input device 46 may be connected to a display or other userinterface (not shown), such display or the like does not show orotherwise indicate the current access code value directly to the user.

Instead, the current access code value is displayed or presented by theseparate reference device 60, which in a preferred method of use isgenerally located remotely from the lockset or locksets 40. Referringagain to FIG. 1, such a separate reference device 60 may be kept in aremote location such as a real estate office 34, but it will be apparentthat the device 60 may instead be carried by a real estate agent orother authorized user for one or more purposes described herein below.FIG. 5 is a front view of the reference device 60 of FIG. 2. As showntherein, the reference device 60 may be small in size, to make it easyto carry on one's person, and includes a digital display 62 for visuallypresenting a numeric value to a user. Although not illustrated, thereference device 60 also includes internal circuitry for generating orcontrolling the numeric value that is presented to the user on thedigital display 62. A reference device 60 suitable for use in thepreferred embodiments of the present invention may be available from, ordeveloped using technology available from, RSA Security Inc. of Bedford,Mass.

Although not shown, it will be appreciated by the Ordinary Artisan thatthe reference device 60 need not be a dedicated, special-purpose devicebut may be, for example, a personal digital assistant (“PDA”), personalcomputer (“PC”), telecommunications device, or the like. Indeed,different types of reference devices 60 may be used in a single systemimplementing one or more embodiments of the present invention.

Importantly, the internal circuitry of the reference device 60 uses thesame method of determining or controlling the numeric value that theelectronic code module 50 does to determine or control the dynamicaccess code. That is, if the electronic code module 50 uses apseudorandom number generator, seeded using one or more predeterminedinputs, to create a series of pseudorandom numbers that are sequentiallyoutput as the dynamic access code, then the reference device 60 alsouses a pseudorandom number generator, seeded using the same one or morepredetermined inputs, to create the same series of pseudorandom numbers.Similarly, if a multiplicity of predetermined numbers, each of a desirednumber of digits, are stored in the electronic code module 50 forsequential output, one at a time, to the control module 50, then thereference device 60 uses the same set of predetermined numbers andoutputs them in the same sequence. Further, the reference device 60 issynchronized with the electronic code module 50 such that the samenumeric value is produced and output, to the digital display 62 and thecontrol module 52, respectively, at the same time, thereby ensuring thatthe numeric value that is visually presented to the user on the digitaldisplay 62 is identical to the current value of the dynamic access code.Thus, a user who is aware of the numeric value that is presented on thedigital display 62 of the reference device 60 at any given moment mayinput that value into the control module 52, via the user input device46, in order to cause the lockset 40 to be unlocked.

As described previously, in one algorithmic approach suitable for use inthe present invention, the electronic code module 50 uses as inputs theyear, month, hour and minute from an internal clock and the three-digitvalue unique to a particular lockset 40 and generates a 4-digit outputvalue using conventional logical operations, such as shifts, rotates,ANDs, ORs, XORs and the like. Assuming the internal clock in thereference device 60 is synchronized with the internal clock of theelectronic code module 50, or the equivalent thereof, the determinationof the 4-digit output value generated by the electronic code module 50may be easily accomplished by the reference device 60.

In at least some embodiments of the present invention, variations ininternal clock values and lag times in reading and inputting code valuesmay be addressed by keeping track, in the electronic code module 50, ofthree successive code values, wherein if a user enters any of the threecode values, the lockset 40 is unlocked. Preferably, the middle value ofthe three successive values is considered to be “current” and issynchronized as accurately as possible with the operation of thereference device 60 and the current code value provided thereby.However, if the code value provided by the reference device 60 leads orlags the same value being considered current in the electronic codemodule 50, it may still be used to unlock the lockset 40 if it isentered just before or after it becomes the “current” value in theelectronic code module 50. Thus, a user who accidentally delays enteringthe code provided by a listing agent, as described below, may still begranted access without the synchronization between the reference device60 and the electronic code module 50 being precise. Internal clocks thatare accurate to +/− one second per month should be sufficient,particularly when coupled with means for manually adjusting the clockvalue as necessary.

In a typical implementation of the present invention, a builderundertakes the process of constructing and selling a small number ofhouses 32 in a type of development often referred to as an “infill”development or project 30. Because so few houses 32 are involved, it isoften not cost-effective to hire an onsite real estate agent to greetpotential buyers, give them information about the house or houses 32,and authorize them to tour the home interiors. Instead, the buildercommonly hires or contracts for a “listing” or “showing” agent who isstationed offsite but is available to meet potential buyers or to talkto them via telephone or other communication means. The builder installsan electronically-controlled lockset 40 of the present invention on anexterior door 14 of each house 32, and provides the listing agent with areference device 60 that is synchronized with the various locksets 40.The lockset 40 may be installed directly onto or into, for example, thefront door 14 of the house 32, using the conventionally drilled holethat is already intended for a lockset 20. The builder may choose to useeither the building-in-process door or the finished decorative door,each of which is well known to the Ordinary Artisan. Finally, thebuilder or the listing agent preferably installs a sign 36 or otherwiseprovides information that may be used by potential buyers to learn howto contact the listing agent to discuss and possibly tour one or more ofthe houses 32.

It will be appreciated that a single reference device 60 may besynchronized or otherwise coordinated with a plurality of locksets 40 inmore than one way. In a first arrangement, the various locksets 40 aresynchronized with each other and with the single reference device 60such that the same numeric value is produced and output to eachrespective control module 52, and to the digital display 62 of thereference device 60, at the same time, thereby ensuring that the numericvalue that is visually presented to the user on the digital display 62is substantially always identical to the current value of the dynamicaccess code in each lockset 40. Thus, a user who is aware of the numericvalue that is presented on the digital display 62 of the referencedevice 60 at any given moment may input that value into the controlmodule 52 of any of the locksets, via the respective user input device46, in order to cause the lockset 40 to be unlocked.

In another arrangement, however, the various locksets 40 aresynchronized with a single reference device but are not synchronizedwith each other. Instead, a multiplexing reference device (not shown)includes internal circuitry for generating or controlling a differentseries of numeric values that may be presented, one at a time or morethan one at a time, to a user on a digital display of the multiplexingreference device. The multiplexing reference device also provides means,such as one or more user inputs or one or more additional displayelements, for determining, controlling or otherwise associating eachnumeric value presented on the digital display with a corresponding,synchronized lockset 40 of the plurality of locksets 40. Thus, themultiplexing reference device is capable of presenting to the user, viathe digital display, the current value of any of the dynamic access codefor any of the plurality of locksets 40, and is capable of doing so in amanner which associates each dynamic access code displayed with thelockset 40 to which it corresponds. This arrangement provides additionalsecurity in that each lockset 40 may be seeded with a different number(for an electronic code module 50 using a pseudorandom generator) orprovided with a different set of predetermined numbers (for anelectronic code module 50 storing and supplying numbers from such amultiplicity of stored numbers), but with which a single referencedevice may be utilized. The underlying technology for a multiplexingreference device suitable for use in the preferred embodiments of thepresent invention may be available from, or developed using technologyavailable from, RSA Security Inc. of Bedford, Mass. It will also beapparent that other arrangements may also be utilized to accomplish thesame function described in these two arrangements.

Regardless of the arrangement of the above-described or referencedarrangements that is used, a potential buyer thereafter arrives at thedevelopment 30 and is or becomes interested in touring the interiorportions of one or more of the houses 32. The buyer may be, but isfrequently not, accompanied by an agent, to whom the buyer may or maynot be contractually bound. Using the contact information provided onthe sign 36, the buyer (or if accompanied, the buyer's agent) mayestablish communication with the listing agent. The listing agent mayanswer the buyer's or his agent's questions about any of the houses 32,and if the buyer or buyer's agent expresses interest in a tour, thelisting agent may vet or screen the buyer using any desiredqualification procedure. The qualification procedure may involve aformal qualification process, established in advance and well known tothe listing agent or the listing agent's personnel. The qualificationprocedure may further include input from, or be approved by, thebuilder.

Once the buyer (or buyer's agent) has passed whatever criteria areestablished in the qualification procedure, the listing agent locatesthe reference device 60 (or multiplexing reference device) correspondingto the lockset 40 for the selected house 32, views the numeric valuethat is presented on the digital display 62 of the reference device 60at any given moment and provides it to the buyer (or buyer's agent) viathe communication method that has been established. The buyer may thenpromptly input that value into the control module 52, via the user inputdevice 46, in order to cause the lockset 40 to be unlocked. If thecommunication method being used permits verbal communication, thelisting agent can stay on the phone to give the buyer a verbal tour.Alternatively, or subsequently, the listing agent may haltcommunications and reinitiate them later in order to receive feedback.

Most preferably, the lockset 40 relocks automatically upon closing orafter a predetermined period of time. The relocking feature preferablyprohibits the buyer from taking a second look at the house 32 withoutcontacting the listing agent again for another code. Thus, no physicalkey is required to relock the lockset 40, thereby minimizing oreliminating the possibility of a key being misplaced or stolen and thenightmares thus created for the builder.

The operation of the dynamic electronic door lock control system isillustrated in FIGS. 6, 7 and 8. FIG. 6 is a simplified flowchartdiagram illustrating steps of a process 6000 generally carried out byeach lockset 40, FIG. 7 is a simplified flowchart diagram illustratingsteps of an alternative process 7000 generally carried out by eachlockset, and FIG. 8 is a very simplified flowchart diagram of the stepsof a process 8000 carried out by users in using the lock control system.Referring first to FIG. 6, the control module 52 may operate in asoftware loop wherein it awaits, at step 6005, the receipt of a codevalue entered by a user via the user input device 46. If at step 6005the control module 52 determines that the user input device 46 hasreceived an entry, then at step 6015 it determines whether the valueinput via the user input device 46 matches the current value of the codeas provided by the electronic code module 50. If so, then at step 6020the lock interface 54 causes the lock mechanism to unlock the door 14.Furthermore, at step 6025, the lock mechanism relocks the door 14immediately, and processing may loop back to the beginning again. On theother hand, so long as no user-input code value is detected at step6005, the control module 52 continues to idle, except that as shown atstep 6010, the electronic code module 50 provides the control module 52with a new value for the code on a periodic, relatively high frequencybasis, which in at least some embodiments is 120 seconds.

As shown in FIG. 7, an additional security and/or reliability functionmay optionally be provided in an alternative process 7000 as shown atsteps 7030 and 7035. Specifically, the control module 52 keeps track ofhow long it has been in operation and, if a predetermined period of timehas elapsed, then the control module 52 shuts down normal operation ofthe lockset 40. Preferably, a special code is then required toreinitiate normal operation. It will be apparent that the length oftime, which in the illustrated process 7000 is shown to be 365 days, maybe varied as desired, and in fact the lockset 40 may be designed topermit the user to manually adjust the length of time as desired. Thisfeature may be utilized to provide additional control over the ongoinguse of the system, examples of such control being described hereinbelow. In particular, this feature prevents unauthorized use of thesystem by halting operation of the lockset 40 after the specified periodof time has elapsed. Although not shown, means is preferably furtherprovided for reactivating the lockset 40 if desired. In at least someembodiments of this implementation, the reference device 60 (and anyother locksets 40 being used therewith) may continue to work.

On the other hand, a function similar to that provided by steps 7030 and7035 (i.e., the ability to prevent unauthorized use of the system afterthe specified period of time has elapsed) may alternatively, and perhapspreferably, be provided by the reference device 60. More particularly,and although not shown, the reference device 60 may keep track of howlong it has been in operation and, if a predetermined period of time haselapsed, then normal operation of the reference device 60 is disabled.Preferably, a special code is then required to reinitiate normaloperation. If the reference device 60 does not have a user input device,then it may be necessary to transmit the code to the device 60wirelessly, or to replace the reference device 60 with a new unit. Itwill be apparent that the length of time, which may, for example, be 365days, may be varied as desired, and in fact the reference device 60 maybe designed to permit the user to manually adjust the length of time asdesired. As with the feature described with regard to FIG. 7, thisfeature may be utilized to provide additional control over the ongoinguse of the system, examples of such control being described hereinbelow. In particular, this feature prevents unauthorized use of thesystem by halting operation of the reference device 60 after thespecified period of time has elapsed. Although not shown, means ispreferably further provided for reactivating the reference device 60 ifdesired. In at least some embodiments of this implementation, thevarious locksets 40 may continue to work.

As described previously, FIG. 8 is a very simplified flowchart diagramof the steps of a process 8000 carried out by users in using the lockcontrol system. As shown therein, the process 8000 begins at step 8005when a home buyer identifies a particular house 32, equipped with adynamic electronic door lock control system of the present invention,that the buyer would like to tour. At step 8010, the buyer calls orotherwise contacts the listing agent via the phone number or othercontact information displayed on the sign 36. Assuming at step 8013 thatthe listing agent has not screened the buyer before, then at step 8014the agent screens the buyer using whatever screening process has beenchosen. If, at step 8018, the buyer passes successfully through theprocess, then the listing agent checks his or her reference device 60for the current code value presented therein and orally or otherwisemanually provides the value to the buyer as shown at step 8019.Separately, the listing agent preferably captures, as represented atstep 8020, the information, such as the buyer's name and phone number,that has been gathered during the screening process for future follow-upor other desired action. Meanwhile, as shown at step 8025, the buyerenters the code value provided by the listing agent in the user inputdevice 46, which if done in a timely manner causes the lockset 40 tounlock at step 8030 (and to relock immediately thereafter).

Because the lockset 40 preferably relocks immediately after the buyerenters, and because the dynamic access code for the lockset 40 changesquickly such that the numeric value previously provided by the listingagent would no longer correspond thereto, the buyer must contact thelisting agent if at step 8036 the buyer wishes to re-enter the house 32.Because at step 8013 the buyer has already been screened, the agent needonly provide the buyer with a new code value as shown at step 8019. Itwill be appreciated, however, that the agent may choose to query thebuyer as to why the buyer needs re-entry and to refuse re-entry incertain circumstances. The screening process may also be omitted if atstep 8037 the same buyer wishes to view other houses 32 and identifies ahouse 32 listed with the same agent. Of course, if the identified house32 is not listed with the same agent, then at step 8013 the buyer willpresumably need to be screened again by the new agent.

The dynamic electronic door lock control system of the present inventionmay also be used in larger developments, e.g., large new subdivisionshaving an on-site agent responsible for showing large numbers of newlyconstructed homes to walk-in prospective buyers. In such an environment,a single agent may be unable to handle all of the customer traffic, andin particular may be unable to both staff a central office and take thetime to leave the central office in order to lock and unlock homes forprospective buyers to view. The dynamic electronic door lock controlsystem of the present invention may be implemented in this environmentin somewhat similar fashion to that of the small infill development,i.e., by installing an electronically-controlled lockset 40 of thepresent invention on an exterior door 14 of each house 32 in thedevelopment, and provides the listing agent with a reference device 60that is synchronized with the various locksets 40. Once again, thelockset 40 may be installed directly onto or into, for example, thefront door 14 of the house 32, using the conventionally drilled holethat is already intended for a lockset 20, and the builder may choose touse either the building-in-process door or the finished decorative door,each of which is well known to the Ordinary Artisan. Because thedevelopment has an on-site agent, and typically a central office inwhich the agent works, the builder typically has no need to provideprospective buyers with any additional information about the lockcontrol system. Instead, the on-site agent may conduct any desired levelof screening, or even no screening whatsoever, before providing theprospective buyer with the value, taken from the reference device 60,that is appropriate to open the door 14 of a selected house 32.Alternatively, because the lockset 40 is preferably self-locking, theagent may choose to accompany the prospective buyer to a selected house32, consult the reference device 60 for the appropriate value to be usedto unlock the lockset 40 and open the door 14, and then leave theprospective buyer alone in the house 32 while the agent returns to thecentral office. When the buyer finishes viewing the house 32, he or shemay simply close the self-locking door 14 behind them, and will beunable to gain access to the house 32 again without contacting the agentfor a new value from the reference device 60.

It will be appreciated that although as described herein the locksets 40are being used only on doors 14 of new houses 32 or houses beingrenovated, many of the teachings of the present invention are likewiseapplicable to other situations. The system of the present invention may,for example, be used with other types of residential home sales, such asindividual existing home sales of conventional type; with other types ofbuildings, such as commercial properties; and with other types oftransactions, including leases and rentals.

A wide variety of additional applications for the dynamic electronicdoor lock control system of the present invention are also envisioned.For example, vacation property owners and property management companiesare often faced with the problem of distributing keys to theirproperties to the guests staying in them. Such owners and managers mayinstall and utilize the system to provide guests with initial access totheir properties, and may then leave the keys to the properties inside.Upon arrival at the property, the guests may contact the owner or aproperty manager, as appropriate, to request the then-current value ofthe access code for the lockset 40. If the guest is unknown to the owneror property manager, then they may choose to use an appropriatescreening or qualification procedure to ensure that the guest isauthorized to enter the home. If the guest passes the qualificationprocedure, the owner or property manager looks up, for that property,the numeric value that is presented on the digital display 62 of thereference device 60 at any given moment and provides it to the guest viasuitable communications method. The guest may then input that value intothe control module 52, via the user input device 46, in order to causethe lockset 40 to be unlocked. Optionally, the owner or property managermay then direct the guest to the location of the keys left in theproperty and provide the guest with any other appropriate information.Because the access code changes frequently, the guest must subsequentlyutilize the property keys to access the property or else contact theowner or property manager for assistance.

The dynamic electronic door lock control system of the present inventionmay also appeal to property owners and property managers who wish togive one-time or limited, non-recurring access to handymen, repairmen,and the like. Suitable properties for such an application may includevacation properties as described above, schools, churches, localgovernment buildings and the like that remain locked much of the timebut for which temporary access needs to be provided on an irregularbasis. Once again, upon arrival at the property, the authorized visitormay contact the owner or a property manager, as appropriate, to requestthe then-current value of the access code for the lockset 40. If thevisitor is unknown to the owner or property manager, then they maychoose to use an appropriate screening or qualification procedure toensure that the visitor is authorized to enter the home. If the visitorpasses the qualification procedure, the owner or property manager looksup, for that property, the numeric value that is presented on thedigital display 62 of the reference device 60 at any given moment andprovides it to the visitor via suitable communications method. Thevisitor may then input that value into the control module 52, via theuser input device 46, in order to cause the lockset 40 to be unlocked.Because the access code changes frequently, the visitor must contact theowner or property manager for assistance every time he needs to re-enterthe building.

FIG. 9 is a simple block diagram of a dynamic electronic door lockcontrol system in accordance with another preferred embodiment of thepresent invention. As shown therein, the door lock control system mayalternatively include a plurality of dynamic electronically-controlledlocksets 40 and a plurality of reference devices 60. In the illustratedexample of this embodiment, there are three electronically-controlledlocksets 40 and three reference devices 60, with each reference device60 being dedicated to a particular lockset 40. The use of separatereference devices 60 may cause greater logistical issues for the listingagent, builder, property manager or owner trying to keep up with all ofthem, but may result in less confusion for the listing agent about whichlockset 40 corresponds to a particular numeric value being displayed by,for example, a multiplexing reference device.

FIG. 10 is a simple block diagram of a dynamic electronic door lockcontrol system in accordance with yet another preferred embodiment ofthe present invention. As shown therein, the door lock control systemmay alternatively include a single dynamic electronically-controlledlockset 40 and a plurality of reference devices 60. In the illustratedexample of this embodiment, there is one electronically-controlledlockset 40 and three reference devices 60, with each reference device 60being synchronized with the single lockset 40. This embodiment permitsmultiple personnel for the listing agent to be able to carry a referencedevice with them, thereby enabling any of multiple personnel to screenthe prospective buyer, buyer's agent, guest or other visitor and toprovide such person with the proper code. Such an approach helpsminimize the possibility of a buyer being unable to view a house 32because of the unavailability of the listing agent at the time, or aguest or other visitor being unable to enter a property because of theunavailability of the owner or property manager at the time.

Although not illustrated, it will be apparent that the embodiments shownin FIGS. 2, 9 and 10 may be combined together as desired. For example,each of several personnel for a listing agent may carry a multiplexingreference device that may be used to provide current codes to buyers forany of several locksets 40. Such combinations may also be useful in theother contexts and applications described.

In another aspect of the present invention, a unique business method isproposed in which a single entity may be the exclusive distributor of alockset product designed and produced according to the above-describedteachings. The distributor sells, licenses, franchises or otherwisegrants exclusive or non-exclusive rights in and to particular geographicareas, such as zip codes. The zip code rights-holders preferably buy orlease units of the dynamic electronic door lock control system of thepresent invention from the distributor, contract with builders to allowsuch rights-holder to list their homes 32 with them, and mount thelocksets 40 on the doors of the builders' houses 32 accordingly. Listingagents can use such a method to build and/or secure market share usingtheir rights in the system of the present invention. Other geographicareas to which this approach may be applied include countries, states,counties, cities or other municipalities, telephone area codes, and thelike.

Alternatively, of course, one or more entities could be distributors ofa lockset product designed and produced according to the above-describedteachings, and each distributor could sell or license the product towhomever they wish, with each purchaser/licensee being unrestricted inwhere the product may be used (i.e., no geographic limitations placed onthe product). Listing agents may choose to purchase the product as amarketing advantage as they offer their services to builders orhomeowners, or builder or homeowners may purchase the productthemselves. With no geographic restrictions in place, a single agent maybe able to cover all of a particular builder's needs across every zipcode in a city or other geographic area. Moreover, distribution of theproduct could be limited to agents only, builders only, homeowners only,or any combination of the three, in order to capitalize on additionalmarket benefits and advantages.

In another aspect of the present invention, another unique businessmethod is proposed in which a single distributor licenses use of thesystem on the basis of a first fee for one part of the system and asecond fee for a second part of the system. One of the fees may be aone-time charge, while the other fee may be a recurring one. Forexample, the distributor/licensor may charge an annual licensing fee foruse of a single reference device 60, and further charge a single,one-time cost for each lockset 40 purchased for use with that referencedevice 60. Such an arrangement could be utilized in the implementationin which all of the locksets 40 that are purchased with the referencedevice 60 are synchronized to operate together, or the implementationwhere each lockset 40 operates independently from the others but thereference device 60 is equipped to work separately with all of them. Inthis arrangement, the locksets 40 may be the purchaser/licensee's tokeep, and could be designed to permit ongoing use independent of thereference device 60, but the reference device 60 itself could utilizethe feature described previously wherein normal operation of the device60 is disabled after a predetermined period of time has elapsed. Forease in design and construction and expediency in implementation of thismethod, it is preferred that the distributor/licensor reference device60 is merely replaced, rather than updated with a special code orotherwise modified. This may be accomplished by overnight shipping areplacement reference device 60, valid for the following license period,near the end of the current license period (assuming the license fee hasbeen paid, or the distributor/licensor is otherwise satisfied with theagreement and agrees to renew the license).

In a numerical example of the foregoing, a purchaser/licensee may chooseto license a single reference device 60 and to order three correspondinglocksets 40. At an annual license fee of $1000 per reference device 60and a one-time cost of $200 per lockset 40, the purchaser/licensee wouldowe a total of $1000+(3×$200)=$1600 for the first year, and $1000 foreach year thereafter that the license is renewed. At the same rates, apurchaser/licensee may choose to license two reference devices 60 and toorder six corresponding locksets 40 (three for each reference device60). This purchaser/licensee would owe a total of(2×$1000)+(6×$200)=$3200 for the first year, and $2000 for each yearthereafter that the licenses are renewed. Discounts could be applied foreach extra lockset 40 purchased, each extra reference device 60licensed, or both.

In still another aspect of the present invention, another uniquebusiness method is proposed in which the system is used (or licensed foruse) by one or more entities in a call center environment. Each suchentity distributes locksets 40 to agents, builders, homeowners, or anycombination of the three, and also establishes one or more call centersthat are equipped with the reference devices 60 corresponding to thevarious locksets 40. Each call center may handle requests for access toproperties that are owned or controlled by multiple different entities.For example, the entity controlling the call center may contract withvarious builders to handle property access requests for all of theirrespective locksets 40. Thus, the entity controlling the call center isseparate from the entity that owns, builds, manages or lists theproperties themselves. Call center services may be offered to builders,real agents, property managers, property owners, and the like. Revenuesmay be generated through the sale of locksets 40, license fees based onlocksets 40, license fees from reference devices 60, license fees basedon number of properties handled, license fees from number of propertyaccesses granted, commissions from home sales, license fees for settingup call centers, and a variety of other measures. Further, although notshown herein, the functionality of the reference devices 60 may bereplaced in such call centers by an integrated system that may trackcode values for large numbers of locksets 40 and may display informationabout each lockset 40 upon request. Such an integrated system mayfurther include a variety of additional software and hardware featuressuch as call tracking, report generation, grouping by entity, historicalaccess information, screening information, an interface to the MLSsystem and/or to an agent's website or other information, and many othertypes of data.

It will be appreciated that a variety of dynamic electronic door lockcontrol systems and/or methods may be offered. For example, as shown inFIG. 11, a “traditional” method, described hereinabove, is when acustomer drives up to a home 12,32 enabled with a lockset 40 and gainsinstant access by calling the call center phone number, which ispreferably found on the signage. Once the caller's identity is verified,for example through a series of questions, a code (typicallyfour-digits) is given to the prospective buyer to punch into the lockset40 to make it operable. The caller may be encouraged to stay on the lineand tour the home with the call center rep.

In another approach, in accordance with other preferred embodiments ofthe present invention, a smart phone (or other intelligent mobiledevice) and a mobile application may be utilized to provide access to ahome. In one such method, a method starts with a prospective buyeropening a mobile application on his or her phone when they arrive at thehouse 12,32 equipped with the technology. They enter the property numberinto the application and then are prompted to verify their identity. Theidentify verification process offered by the application may beautomated. They can either choose the call center verification approach,such as the one described above, or verify using their credit cardinformation stored locally on the phone. In some embodiments, at leastsome of the verification process may be executed ahead of time, so thatonce initially verified, the user needs only to enter a passcode, answera secret question, provide other identifying information, or the likewithout having to go back through the entire verification process. Onceverified (or re-verified), the prospective buyer or other user may beprovided access to the core functions of the mobile application. Inparticular, once the property number (or other property identificationinformation) is entered into the application, the user may receive theaccess code on the screen of the smart phone. The user may then enterthe access code into the lock to gain access to the home, as describedpreviously.

In still another approach, in accordance with other preferredembodiments of the present invention, a smart phone (or otherintelligent mobile device) and a mobile application may be utilized withan alternative lockset enabled with suitable communication protocols,such as near field communications (NFC) protocol, in order to provideaccess to a home. One such method starts with a prospective buyeropening a mobile application on his or her phone when they arrive at thehouse 12,32 equipped with the technology. They enter the property numberinto the application and then are prompted to verify their identity, asdescribed in the preceding paragraph, and once verified (orre-verified), the prospective buyer or other user may be provided accessto the core functions of the mobile application, also as describedpreviously. In particular, once the property number (or other propertyidentification information) is entered into the application, theprospective buyer or other user may swipe their smart phone to gainaccess into the house 12,32. The swipe delivers the code to the phoneand the prospect transfers/punches it into the lock, or the swipe itselfcauses the lock to unlock. The code may or may not appear on the screenof the smart phone in conjunction with this operation. NFC technologysuitable for use in this and other preferred embodiments of the presentinvention are described in U.S. Pat. No. 7,706,778 to Lowe, issued Apr.27, 2010 and titled “SYSTEM AND METHOD FOR REMOTELY ASSIGNING ANDREVOKING ACCESS CREDENTIALS USING A NEAR FIELD COMMUNICATION EQUIPPEDMOBILE PHONE,” the entirety of which is incorporated herein byreference.

In another approach, in accordance with still other preferredembodiments of the present invention, a website is provided and may beaccessed by a prospective buyer. The website may be a conventional realestate website offered by a developer, individual real estate agent,real estate agency, or the like, or may be a specialized website offeredby a proprietor of the technology described herein. The website may listproperties for sale and identify those which feature the presenttechnology, may provide a specific list of those properties whichfeature the present technology, or both. When a prospective buyer ortheir agent accesses the website and selects one or more propertiesenabled with the present technology for viewing, they have the option ofverifying their identify online. By verifying online, the agent orprospective buyer will hasten the process of the traditional method.Once at the door, the agent or buyer need only to enter a passcode,answer a secret question, provide other identifying information, or thelike in order to receive the access code. Besides the code, the sitecould also provide driving directions and house details for prospects.

If the website is being accessed from a mobile device, such that theaccess code may be immediately entered into a lockset such as thelockset 40 described previously, then the systems and methods describedpreviously may be utilized. Alternatively, the access code may be apre-determined, one-time use code. In some embodiments, the same codemay be utilized with multiple different houses 12,32. In some of theseembodiments, a “tour” of houses 12,32 equipped with the presenttechnology may be established, and the same code could be used with allof the houses 12,32 in the tour.

In another embodiment, in accordance with still other preferredembodiments of the present invention, a smart phone (or otherintelligent mobile device) and a mobile application may be used to offera prospective buyer or other user a list of additional propertiesequipped with technology of the present invention. The additionalproperties included in such a list may be limited to properties offeredby a particular realtor, properties offered by a particular real estatecompany, properties offered by a particular builder, properties offeredby a particular developer, properties equipped with technology of thepresent invention under the authority of an owner or licensee of suchtechnology, or any other suitable collection of properties. Furthermore,the application may incorporate geographical location information suchthat the list of properties is limited to nearby properties. In at leastsome of these embodiments, information about several such nearbyproperties may be downloaded, texted, or the like to the device (or, insome embodiments, to one or more other designated devices). Suchinformation may include, but is not limited to, directions, maplocation, tour information (i.e., a recommended order in which to seethe properties), simple address information, and the like. Furthermore,the application may utilize a GPS device in the smart phone to formulateor provide map and/or direction information from one property toanother.

In another embodiment, variation, or feature, a lockset may be providedwith a sticker, disposed on the exterior thereof, that is an NFC device.Users may swipe their phone over the NFC sticker which will do one ormore of the following:

-   -   For Verification:        -   Take users to the Call-A-Key 2.0 public facing website            verification page        -   Take users to a Call-A-Key Mobile Application (such as            applications running on smartphones, tablets, and/or similar            mobile computing devices) for verification and future home            tours        -   Connect directly to Call Center via Chat or voice over IP            (VoIP)        -   Provide option to call the Call-Center    -   For Receiving the Opening Code which is punched in by the user.

In another embodiment, variation, or feature, an NFC device may beintegrated into a lockset. A user may swipe their phone over thelockset, and in conjunction with a mobile application, carry out one ormore following:

-   -   A user may be able to pre-determine their verification online        using a corresponding website and this information may also be        shared with the mobile application. This may enable the        application to pair with the NFC enabled lockset such that it        may be unlocked using only swipe technology rather than by        physically entering the access code.    -   A user may swipe his phone on the NFC enabled lockset, causing        it to download and/or open the mobile application. The user may        then be verified based on information from one or more        categories, including credit card information stored in the        phone, phone number, other personal information, and the like.    -   A user may be verified or rejected. If verified, the application        may enable the phone to be swiped for access control and the        unit will unlock granting access.

In another embodiment, variation, or feature, a lockset may include awireless card. A user may call, use NFC, or the like to request anaccess code to open the lock. After verification, a unique, one-time usecode may be created by a server and sent to the user's phone and to thelock simultaneously (or in close proximity to each other). The code maybe entered by the user entering it manually into the lockset, or byswiping the phone, using NFC or other technology, into the lockset.

Based on the foregoing information, it is readily understood by thosepersons skilled in the art that the present invention is susceptible ofbroad utility and application. Many embodiments and adaptations of thepresent invention other than those specifically described herein, aswell as many variations, modifications, and equivalent arrangements,will be apparent from or reasonably suggested by the present inventionand the foregoing descriptions thereof, without departing from thesubstance or scope of the present invention. Accordingly, while thepresent invention has been described herein in detail in relation to itspreferred embodiment, it is to be understood that this disclosure isonly illustrative and exemplary of the present invention and is mademerely for the purpose of providing a full and enabling disclosure ofthe invention. The foregoing disclosure is not intended to be construedto limit the present invention or otherwise exclude any such otherembodiments, adaptations, variations, modifications or equivalentarrangements; the present invention being limited only by the claimsappended hereto and the equivalents thereof. Although specific terms areemployed herein, they are used in a generic and descriptive sense onlyand not for the purpose of limitation.

We claim:
 1. A method of controlling access to a building, comprising:installing an electronically-controlled lockset on an exterior door of abuilding, wherein a locking mechanism of the electronically-controlledlockset is disposed in an operable relationship with a door frame inwhich the exterior door is installed and the state of the lockingmechanism controls whether the exterior door may be opened, wherein theelectronically-controlled lockset is configured to release the lockingmechanism upon an access code being entered into theelectronically-controlled lockset, wherein the access code is valid forreleasing the locking mechanism for a predetermined window of time;maintaining a reference device at a separate location that is locatedremotely from the building, the reference device being configured togenerate a current value of the access code, wherein the current valueof the access code is time-synchronized with theelectronically-controlled lockset; and providing the current value ofthe access code to a user in response to a request from the user for theaccess code to access the building.
 2. The method of claim 1, whereinthe electronically-controlled lockset is configured to receive theaccess code via a near field communication (NFC) transmission.
 3. Themethod of claim 1, wherein the access code is based at least in part onan output of a pseudorandom number generator function.
 4. The method ofclaim 1, wherein the access code is based at least in part on a currenttime.
 5. The method of claim 1, wherein the access code comprises anumeric code.
 6. A system for controlling access to a building,comprising: a computing device; an application executable on thecomputing device, wherein the application comprises: logic thatgenerates an access token for the building in response to receiving arequest for the access token from a client device; and logic thattransmits the access token to the client device.
 7. The system of claim6, wherein the request for the access token comprises an identifier ofthe building and the logic that generates the access token furthercomprises: logic that determines whether the identifier is valid; andlogic that, in response to a determination that the identifier is valid,generates the access token based at least in part on the identifier,wherein the access token is limited to the building.
 8. The system ofclaim 6, wherein the request for the access token comprises a timestampof the request and the logic that generates the access token furthergenerates the access token based at least in part on the timestamp,wherein the access token is valid for a predefined window of timesubsequent to a time specified by the timestamp.
 9. The system of claim6, wherein the application further comprises: logic that determines thatthe building has been accessed based upon an electronic message sentfrom an electronic lock, wherein the electronic message specifies thatthe electronic lock has received the access token; and logic thatrecords that the building has been accessed.
 10. The system of claim 6,wherein the application further comprises logic that authenticates theclient device, wherein the access token is generated in response to adetermination that the client device is approved to receive the accesstoken.
 11. The system of claim 6, wherein: the access token is acurrently valid access token; and the logic that generates the accesstoken for the building in response to receiving the request for theaccess token from a client device further comprises logic thatperiodically generates a new access token, wherein the new access tokenreplaces a previously generated access token as the currently validaccess token.
 12. The system of claim 6, wherein the request from theclient device comprises a client identifier and the application furthercomprises logic that determines that the client device corresponds to aregistered client device based at least in part on the client identifierincluded in the request.
 13. An apparatus for controlling access to abuilding, comprising: an input mechanism configured to receive an accesstoken; an electronically-controlled locking mechanism communicativelycoupled to the input mechanism, wherein the electronically-controlledlocking mechanism is configured to enter an unlocked state in responseto the input mechanism receiving a valid access token; and tokenvalidation circuitry communicatively coupled to the input mechanism andthe electronically-controlled locking mechanism, wherein the tokenvalidation circuitry is configured to periodically generate a referenceaccess token and the token validation circuitry is configured to comparethe access token received via the input mechanism to the referenceaccess token to determine whether the access token is valid.
 14. Theapparatus of claim 13, wherein the input mechanism comprises a keypad.15. The apparatus of claim 13, wherein the input mechanism comprises anear field communication (NFC) receiver.
 16. The apparatus of claim 13,wherein the input mechanism comprises a BLUETOOTH receiver.
 17. Theapparatus of claim 13, wherein the reference access token is based atleast in part on a time at which the reference access token isgenerated.
 18. The apparatus of claim 13, wherein the apparatus furthercomprises a unique identifier and the reference access token is based atleast in part on the unique identifier.
 19. The apparatus of claim 13,wherein the valid access token is valid for a predefined period of time.20. The apparatus of claim 13, further comprising network communicationcircuitry, wherein the network communication circuitry is configured toreport to a remote computing device at a time that theelectronically-controlled locking mechanism enters the unlocked stateand the access token used when the electronically-controlled lockingmechanism enters the unlocked state.